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Erratum to “Estimation of drag forces caused by natural woody vegetation of different scales”[journal of Hydrodynamics, 2014, 26(4)]

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journal of Hydrodynamics 2015年第2期27卷 319-319页

作者： jALONEN johanna jrvel juha Department of Civil and Environmental Engineering Aalto University

This is the erratum to the article [jALONEN johanna, jrvel juha, journal of Hydrodynamics, 2014, 26(4)]. In pages 610 and 621 the drag coefficients are corrected.

关键词： Erratum to Estimation of drag forces caused by natural woody vegetation of different scales

From Finnish Assortment Pricing to Market Economy Using Prices for Sawn Wood and Chips in Reference Bucking

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Open journal of Forestry 2024年第3期14卷 233-280页

作者： juha Lappi Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life Sciences s Norway

Dominant Finnish assortment pricing gives prices for sawlog and pulp wood volumes. Buyers buck stems to sawlogs using secret price matrices. Agreed dimensions allow wide range of sawlog volumes. Forest owners cannot objectively compare biddings: timber trade is a lottery game. Bucking is analyzed in terms of sawlog, pulp wood, log cylinder, sawn wood, value-weighted sawn wood, and chips. Sawn wood and its value are computed from top diameter of the sawlog. Profit maximization requires buyers to buck logs producing smaller than maximal value, causing dead weight loss. Nominal assortment prices have unpredictable relation to effective stumpage price. Assortment pricing does not meet requirements of market economy. If sawmills linked to pulp mills buck smaller sawlog percentages than independent sawmills, as generally believed, they use higher price for chips in their own harvests than they pay for independent sawmills, indicating imperfect competition for chips. Sawn wood potential pricing is suggested which gives prices for sawn wood and chips coming both from sawlogs and pulp wood in reference bucking which maximizes sawn wood for given minimum and maximum log length and minimum top diameter. Simple algorithm generates feasible bucking schedules from which optimum can be selected using any objective. Pricing produces unit price for all commercial wood utilizing ratio of theoretical sawn wood and commercial volume in stand. Unit price can be compared to stem pricing and could be compared to assortment pricing if assortment pricing would produce predictable sawlog percentages. Sawn wood potential pricing is concrete, transparent, easy to compute, considers stem size and tapering, reduces trading cost and is less risky to buyers than stem pricing. It meets requirements of market economy. Readers can repeat computations using open-source software jlp22.

关键词： Sawmill Pulp Mill jlp22 Dead Weight Loss Stem Price

Ion emission from warm dense matter produced by irradiation with a soft x-ray free-electron laser

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Matter and Radiation at Extremes 2024年第1期9卷 71-84页

作者： josef Krása Tomás Burian Vera Hájková jaromír Chalupský Šimon jelínek Katerina Frantálová Michal Krupka Zuzana Kuglerová Sushil Kumar Singh Vojtech Vozda Ludek Vysín MichalŠmíd Pablo Perez-Martin Marion Kühlman juan Pintor jakub Cikhardt Matthias Dreimann Dennis Eckermann Felix Rosenthal Sam M.Vinko Alessandro Forte Thomas Gawne Thomas Campbell Shenyuan Ren YuanFeng Shi Trevor Hutchinson Oliver Humphries Thomas Preston Mikako Makita Motoaki Nakatsutsumi Xiayun Pan Alexander Köhler Marion Harmand Sven Toleikis Katerina Falk Libor juha Department of Radiation and Chemical Physics Institute of PhysicsCzech Academy of SciencesNa Slovance 218221 Prague 8Czech Republic Laser Plasma Department Institute of Plasma PhysicsCzech Academy of SciencesZa Slovankou 318200 Prague 8Czech Republic Department of Surface and Plasma Science Faculty of Mathematics and PhysicsCharles University in PragueV Holesovi ckách 218000 Prague 8Czech Republic Department of Physical Electronics Faculty of Nuclear Science and Engineering PhysicsCzech Technical University in PragueV Holesovi ckách 218000 Prague 8Czech Republic Helmholtz-Zentrum Dresden-Rossendorf Bautzner Landstraße 40001328 DresdenGermany DESY Photon Science Notkestraße 85D-22607 HamburgGermany Institut de Minéralogie de Physique des Matériaux et de CosmochimieUMR 7590–UPMC/CNRS/IRD/MNHNSorbonne Université4 place Jussieu75005 ParisFrance Department of Physics Faculty of Electrical EngineeringCzech Technical University in PragueTechnická216627 Prague 6Czech Republic Center for Soft Nanoscience University of MünsterBusso-Peus-Straße 10D-48149 MünsterGermany Department of Physics Clarendon LaboratoryUniversity of OxfordParks RoadOxford OX13PUUnited Kingdom Central Laser Facility STFC Rutherford Appleton LaboratoryDidcot OX110QXUnited Kingdom Lawrence Livermore National Laboratory 7000 East AvenueLivermoreCalifornia 94550USA European XFEL GmbH Holzkoppel 4D-22869 SchenefeldGermany Technische Universität Dresden 01062 DresdenGermany

We report on an experiment performed at the FLASH2 free-electron laser(FEL)aimed at producing warm dense matter via soft x-ray isochoric *** the experiment,we focus on study of the ions emitted during the soft x-ray ablation process using time-of-flight electron multipliers and a shifted Maxwell–Boltzmann velocity distribution *** find that most emitted ions are thermal,but that some impurities chemisorbed on the target surface,such as protons,are accelerated by the electrostatic field created in the plasma by escaped *** morphology of the complex crater structure indicates the presence of several ion groups with varying *** find that the ion sound velocity is controlled by the ion temperature and show how the ion yield depends on the FEL radiation attenuation length in different materials.

关键词： electrostatic emitted chemi

A comprehensive and up-to-date web-based interactive 3D emergency response and visualization system using Cesium Digital Earth: taking landslide disaster as an example

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Big Earth Data 2023年第4期7卷 1058-1080页

作者： Zhiyuan Yang jing Li juha Hyppa jianhua Gong jingbin Liu Banghui Yang National Engineering Research Center for Geoinformatics Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina College of Resources and Environment University of Chinese Academy of SciencesBeijingChina Department of Remote Sensing and Photogrammetry Finnish Geospatial Research InstituteEspooFiniand State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina

As with the fast advances in the technologies of big Earth data and information communication,Web-based 3D GIS system has come a long way from a few years *** advances reflect in many aspects of 3D GIS such as higher real-time performance,enhanced interactivity,more realistic 3D visualization effect and improved user *** paper aims to present a comprehensive and upto-date 3D Web GIS for Emergency Response using the current *** web application framework and the well-known Cesium APl,taking landslide disaster as an *** upon recent advances in WebGL technology,we developed a suite of enhanced 3D spatial analysis functions,including interactive route planning,instant text/image/video messaging being incorporated into both 3D WebGL page and mobile GIS applications,and progressive 3D construction and AR visualization using LiDAR and camera over local emergency network or ***,professional functions such as landslide susceptibility mapping,landslide monitoring,spatial temporal contingency plan management,landslide information management,personnel and equipment management,and communication are all implemented and integrated in the 3D GIS *** of the functions of the system are implemented using open-source projects,which is beneficial to the development of the 3D GIS research community.

关键词： 3D GIS emergency response landslide Cesium Digital Earth

Estimation of a Linear Model in Terms of Intra-Class Correlations of the Residual Error and the Regressors

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Open journal of Statistics 2022年第2期12卷 188-199页

作者： juha Lappi University of Eastern Finland Joensuu Finland

Objectives: The objective is to analyze the interaction of the correlation structure and values of the regressor variables in the estimation of a linear model when there is a constant, possibly negative, intra-class correlation of residual errors and the group sizes are equal. Specifically: 1) How does the variance of the generalized least squares (GLS) estimator (GLSE) depend on the regressor values? 2) What is the bias in estimated variances when ordinary least squares (OLS) estimator is used? 3) In what cases are OLS and GLS equivalent. 4) How can the best linear unbiased estimator (BLUE) be constructed when the covariance matrix is singular? The purpose is to make general matrix results understandable. Results: The effects of the regressor values can be expressed in terms of the intra-class correlations of the regressors. If the intra-class correlation of residuals is large, then it is beneficial to have small intra-class correlations of the regressors, and vice versa. The algebraic presentation of GLS shows how the GLSE gives different weight to the between-group effects and the within-group effects, in what cases OLSE is equal to GLSE, and how BLUE can be constructed when the residual covariance matrix is singular. Different situations arise when the intra-class correlations of the regressors get their extreme values or intermediate values. The derivations lead to BLUE combining OLS and GLS weighting in an estimator, which can be obtained also using general matrix theory. It is indicated how the analysis can be generalized to non-equal group sizes. The analysis gives insight to models where between-group effects and within-group effects are used as separate regressors.

关键词： Best Linear Unbiased Estimator Ordinary Least-Squares Generalized Least Squares Singular Correlation Matrix Between-Group Effects Within-Group Effects

A lake ice phenology dataset for the Northern Hemisphere based on passive microwave remote sensing

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Big Earth Data 2022年第4期6卷 401-419页

作者： Xingxing Wang Yubao Qiu Yixiao Zhang juha Lemmetyinen Bin Cheng Wenshan Liang Matti Leppäranta College of Urban and Environment Sciences Northwest UniversityXi’anChina Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina International Research Center of Big Data for Sustainable Development Goals BeijingChina FMI-AIR joint Research Center for Arctic Observations Finnish Meteorological Institute and Aerospace Information Research InstituteChinese Academy of SciencesSodankyläFinland Arctic Space Center Finnish Meteorological InstituteHelsinkiFinland Finnish Meteorological Institute HelsinkiFinland Institute of Atmospheric and Earth Sciences University of HelsinkiHelsinkiFinland

Lake ice phenology(LIP)is an essential indicator of climate change and helps with understanding of the regional characteristics of climate change *** observation records and remote sensing retrieval products of lake ice phenology are abundant for Europe,North America,and the Tibetan Plateau,but there is a lack of data for inner *** this work,enhanced-resolution passive microwave satellite data(PMW)were used to investigate the Northern Hemisphere Lake Ice Phenology(PMW LIP).The Freeze Onset(FO),Complete Ice Cover(CIC),Melt Onset(MO),and Complete Ice Free(CIF)dates were derived for 753 lakes,including 409 lakes for which ice phenology retrievals were available for the period 1978 to 2020 and 344 lakes for which these were available for 2002 to *** of the PMW LIP using ground records gave correlation coefficients of 0.93 and 0.84 for CIC and CIF,respectively,and the corresponding values of the RMSE were 11.84 and 10.07 *** lake ice phenology in this dataset was significantly correlated(Pj00076.00081.

关键词： Lake ice phenology dataset Northern Hemisphere passive microwave remote sensing

Interaction between xylanase and a proton pump inhibitor on broiler chicken performance and gut function

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Animal Nutrition 2022年第1期8卷 277-288页

作者： Gemma Gonzalez-Ortiz Sophie A.Lee Kirsi Vienola Kari Raatikainen German jurgens juha Apajalahti Michael R.Bedford AB Vista MarlboroughWiltshireSN84ANUnited Kingdom Alimetrics Ltd. Koskelontie 19 BEspooFinland

Three hundred thirty-six Ross 308 male broiler chicks were used in a 21-d study to explore performance and gut function when treated with a proton pump inhibitor(PPI;0 or 89 mg/kg)in a 2×2 factorial arrangement with a xylanase(Xyl;0 or 0.1 g/kg)to determine if the beneficial activity of arabinoxylan(AX)depolymerisation,through arabinoxylo-oligosaccharides(AXOS)production,starts in the upper gastrointestinal *** with the PPI started from d 14,and by d 21 animal performance had deteriorated(P<0.001).An interaction was observed between PPI and Xyl for feed conversion ratio(FCR)(P<0.05),whereby the combination reduced the negative effect of PPI on *** of PPI raised digesta pH in the gizzard and caecum(P<0.05),increased protein concentrations in the lower gut(P<0.05)and reduced intake of digestible nutrients(P<0.05).Caecal concentrations of indole,p-cresol,ammonia and the ratio of total volatile fatty acid(VFA)to butyric acid were increased with PPI(P<0.05),indicating enhanced protein *** activity in the digesta were greatest in the caeca,especially when Xyl was supplemented(P<0.001).The concentration of total soluble AX was greater in the gizzard and ileal digesta with Xyl supplementation(P<0.05),supporting the depolymerisation action of xylanase even under acidic *** data suggest xylanase may function in the gizzard even though pH is not optimal for activity and emphasises the importance of chlorohydric acid secretions in ensuring overall optimum gut *** depolymerisation benefits animal performance although it is still unknown how the AXOS produced with xylanase supplementation in the upper gastrointestinal tract influence the microbial populations and overall gut functionality.

关键词： Xylanase Proton pump inhibitor Arabinoxylan degradation Protein fermentation Broiler chicken

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Automated registration of wide-baseline point clouds in forests using discrete overlap search

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Forest Ecosystems 2022年第6期9卷 852-877页

作者： Onni Pohjavirta Xinlian Liang Yunsheng Wang Antero Kukko jiri Pyorala Eric Hyyppa Xiaowei Yu Harri Kaartinen juha Hyyppa Department of Remote Sensing and Photogrammetry Finnish Geospatial Research InstituteVuorimiehentie 5Espoo02150Finland The State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan430070China Department of Forest Sciences University of HelsinkiHelsinkiFI-00014Finland Department of Geography and Geology University of TurkuTurkuFI-20500Finland

Forest is one of the most challenging environments to be recorded in a three-dimensional(3D)digitized geometrical representation,because of the size and the complexity of the environment and the data-acquisition constraints brought by on-site *** studies have indicated that the data-acquisition pattern can have more influence on the registration results than other *** practice,the ideal short-baseline observations,i.e.,the dense collection mode,is rarely feasible,considering the low accessibility in forest environments and the commonly limited labor and time *** wide-baseline observations that cover a forest site using a few folds less observations than short-baseline observations,are therefore more preferable and commonly ***,the wide-baseline approach is more challenging for data registration since it typically lacks the required sufficient overlaps between *** now,a robust automated registration solution that is independent of special hardware requirements has still been *** is,the registration accuracy is still far from the required level,and the information extractable from the merged point cloud using automated registration could not match that from the merged point cloud using manual *** paper proposes a discrete overlap search(DOS)method to find correspondences in the point clouds to solve the low-overlap problem in the wide-baseline point *** proposed automatic method uses potential correspondences from both original data and selected feature points to reconstruct rough observation geometries without external knowledge and to retrieve precise registration parameters at *** extensive experiment was carried out with 24 forest datasets of different conditions categorized in three difficulty *** performance of the proposed method was evaluated using various accuracy criteria,as well as based on data acquired from different hardware,platforms,viewing persp

关键词： Close-range sensing Forest Registration Point cloud Wide-baseline Terrestrial laser scanning Unmanned aerial vehicle Drone In situ Discrete overlap search

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The comparison of design airflow rates with dynamic and steady-state displacement models in varied dynamic conditions

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Building Simulation 2021年第4期14卷 1201-1219页

作者： Natalia Lastovets Risto Kosonen juha jokisalo Department of Mechanical Engineering Aalto UniversityEspooFinland College of Urban Construction Nanjing Tech UniversityNanjingChina

A temperature-based method is usually applied in displacement ventilation (DV) design when overheating is the primary indoor climate concern. Different steady-state models have been developed and implemented to calculate airflow rate in rooms with DV. However, in practical applications, the performance of DV depends on potentially dynamic parameters, such as strength, type and location of heat gains and changing heat gain schedule. In addition, thermal mass affects dynamically changing room air temperature. The selected steady-state and dynamic models were validated with the experimental results of a lecture room and an orchestra rehearsal room. Among the presented models, dynamic DV model demonstrated a capability to take into account the combination of dynamic parameters in typical applications of DV. The design airflow rate is calculated for the case studies of dynamic DV design in the modelled lecture room in both dynamic and steady-state conditions. In dynamic conditions of heavy construction in 2–4 hours occupancy periods, the actual airflow rate required could be 50% lower than the airflow rate calculated with the steady-state models. The difference between steady-state and dynamic multi-nodal model is most significant with heavyweight construction and short occupancy period (17%–28%). In cases with light construction, the dynamic DV model provides roughly the same airflow rates for four-hour occupancy period than the Mund’s model calculates. The dynamic model can significantly decrease the design airflow rate of DV, which can result in a reduction of investment costs and electrical consumption of fans.

关键词： displacement ventilation design airflow rate temperature gradient dynamic model simplified building energy models